Closeup florals can be a very rewarding, but you need to have the basics down. Photo 1 has a few issues. Those large rocks need to go, and you need to have less DOF so that those pebbles compliment the catus, not compete with it. I would have tried to move one way or the other to get the pebbles as your only background. Pic 2, those large rocks are really in focus as well as the pebbles, and as in pic 1, need to go . Also the side of the container is very distracting. Pic 3, same as pics 1 & 2, The background of wooden planks need to go, or use DOF to soften it up so it's no longer distracting to the eye.
What I do with my florals, is to study the composition on my LCD screen. I spend as much time looking at the background, as I do composing the picture.
After you take the picture, look at it on your LCD. Look at your composition, look at the background, and look at your exposure using your Histogram if you feel the exposure is off.
Shooting in a closed environment such as a greenhouse is very difficult because the plants which are usually potted, are on right on top of each other. Backgrounds are easily overly complicated with plants, pots, etc. Many times, I just don't take the picture because there isn't anything I can do to correct all the background issues. It's always seems it's the little things that make or break close ups, especially close up florals.
Here's a close up of an Orchid taken in a very cramped greenhouse. I tried to have the background as soft as possible by using shallow DOF, yet making sure that the Orchid is in focus. You'll notice that entire background are flower pots, but they don't compete for the viewers attention.
DSCN2680 by
jaw101, on Flickr